The laymen's general use of the word theory is almost always tied to hunches or non-researched guesses of the unknown. "I think the bookshelf came loose because the cat keeps climbing up on it, but it's just a theory."
While this watered-down definition of theory is perfectly acceptable when dealing with something as trivial and conversational as loosened furniture, it has no place in the world of science. In science, a theory is law, it's fact until you can prove otherwise. Gravity is a theory, too. Feel free to climb out on the roof and take a leap if you don't believe theories are laws or true.
A hypothesis is much closer to what average people mean when they use the word theory. A hypothesis is an educated guess at explaining something that is currently untested or inexplicable, with the intention of testing it with due diligence and experimentation. Once it's positively proved by multiple unrelated sources and can be falsified, then it becomes theory. A theory in this sense is a principle that is agreed upon as correct by the scientific community and can be used as explanation and prediction for a class of phenomena.
When theists disingenuously misuse the word theory to misrepresent what it means, it is grossly irresponsible and spineless. Clearly it's a sign of desperation and perhaps a lack of security in their faith or holy book. But not all theists reject evolution, mostly just creationists. And these morons are truly the bottom of the believer barrel.
But it got me to thinking: If I came face-to-face with one of these dolts, is there a religious term I could use to show them similarly how easily this tactic could be used unfairly? Then it hit me: apologist. If you weren't religious or well-read, you might see or hear the word apologist and think it means someone who apologizes for something. And that would be ignorant.
(As a quick aside, people often get offended when they are called ignorant or told they are ignorant on such things. It merely means they aren't educated on a particular subject; it's not an insult. They are uninitiated or uninformed. I'm ignorant of French cuisine and TV repair. It's no big deal. The funny thing is, if they're insulted by being called ignorant because they think you're calling them stupid, then that's ignorance again.)
So if you then put the adjective "Christian" in front of apologist, you would think that person was apologizing for either Christianity or for being a Christian. (Of course I feel like they really should be apologizing for the atrocities Christianity has committed and continues to commit, but that's not the point of this post.) An apologist is someone who defends something, usually in speech or written word, and a lot of times the subject is unpopular, though that's not necessary. So, when you hear apologist, a synonym for that is defender or advocate.
Just as the insincere theist or creationist throws around "theory" in an effort to belittle evolution, I could just as easily say Christian apologists are apologizing for their religion because it's so ridiculous and harmful. Would that be fair? No. Would it be misleading to sway the audience to a non-believer's side? Yes.
Again, it comes down to education and critical thinking. Think for yourselves. Evolution is fact, look it up and deal with it.